EMAXplus™ monitoring
EMAXplus™ will monitor engine and electrical bus data and provide aural and visual signaling for certain critical and abnormal conditions.
The listed conditions are continuously monitored. All conditions will be indicated by tone and visual indication (CAUTION or MESSAGE flashing). The message is then announced on pilot request (ACK/REQ/SETUP button). Until the message has been played, the tone repeats every 60s. CAUTION remains on steady as long as any condition continues.
The pilot can request the information to be announced by pushing the panel mounted button.

How does it work?
EMAXplus™ reads the engine and electrical bus data measured by the Avidyne EMax system’s SIU or DAU computer. If installed in SIU aircraft it also converts the data to DAU format which is readable by both MFD and PFD, utilizing the enhanced capabilities normally only available in later Avidyne Entegra DAU based installations. At the same time, knowing the electrical and engine parameters, EMAXplus™ is able to provide additional monitoring with voice messages and aural as well as optical signaling.
Parameter | Message ON | Message OFF |
Oil Temperature | at or above 240°F | at or below 235°F |
Oil Pressure | at or below 10 PSI | at or above 15 PSI |
CHT High | any CHT above 420°F for 5s | all CHTs below 401°F |
TIT High (22TN only) |
TIT above 1750°F for 5s | TIT below 1731°F |
Engine Not Ready | OILT < 100°F & RPM > 1000 (2s) | OILT ≥ 100°F or RPM < 950 |
ALT1 Load | at or below 1 A for 20 s | at or above 4 A |
ALT2 Load | at or below 1 A for 20 s | at or above 4 A |
EBUS Low Voltage | at or below 24.4 V DC | at or above 26.4 V DC |
MBUS Low Voltage | MBUS at or below 24.4V for 20 s | at or above 26.4 V |
High Voltage | MBUS or EBUS above 30 V for 20 s | both below 29 V |
ALT1 High Load | above 50A for 5 s | below 45 A |
ALT2 High Load | above 13A for 5 s | below 10 A |
Data Missing | no valid SIU/DAU data for 5 s | SIU/DAU data resumed |
Fuel Timer | every 5 (SR20) / 8 (SR22) gallons | ACK |
Flight Timer | Reset and Start > 2500 RPM | Stop < 1200 RPM |
PITOT Caution | Pitot OFF & OAT ≤ 5°C for 5 s or loss of OAT data |
Pitot ON or OAT above 8°C |
PITOT On | Pitot ON & OAT ≥ 8°C for 5 s | Pitot OFF or ACK |
TKS Activation | every 15 minutes of TKS pump activation [t = (tNORMAL+2* tMAX)] | ACK |